Blend all ingredients in blender, adding water as necessary.
A Vitamix or other high-powered blender is best for this recipe.
serving sizes: originally, this was sized as one very large serving for someone following a whole foods, plant-based diet similar to dr. joel fuhrman's "eat to live" high-volume produce protocol. for those following such a diet-style, you may (like me, and i am a small woman weighing --90lbs) like to make this big "green" smoothie and sip it all morning. the big kicker for caloric content is how much flax you put in -- otherwise, these are mostly nutrient-dense (vs. calorically dense) foods (the soymilk and the banana being higher in calories, relatively, of course). i have since adjusted this for 2-3 servings, since most people would only want one glass for a light breakfast.
substitutions: feel free to make substitutions here. collards stand in nicely for kale, pineapple can be subbed for part of the berries and stands up nicely against the assertive cruciferous greens, raspberries and mango and anything else available work well. my basic formula is banana (creaminess, flavor), greens (mostly for the nutrients), 1-2 kinds of fruit (lower glycemic index than bananas but lots of flavor and nutrients), 1-2T flax (depends on the number of servings, and what else you're eating that day), soymilk (or ricemilk, or nutmilk, or juice -- although nondairy milk will make it creamier and add different nutrient values than extracted fruit juice), and then enough water to blend or ice to chill.
handling greens for smoothies: i take my greens, wash them, and then freeze them (raw) into 3c servings for making smoothies. when i make the smoothie, i simply throw the frozen (uncooked) greens into the smoothie and they blend up especially well. i hear from folks without a blender like vitamix or blendtec that this gets their greens smoother.
blenders: if you do NOT have a high-powered blender, try flaxseed meal instead of the whole seeds. the oil won't give the same benefit as the meal/seeds, and the whole seeds won't be digested and assimilated if they're not broken up properly prior to consumption (although the oil is better than nothing).
a final caveat: i can't stand this with cooked frozen greens. i know people who do this, but i find the end result slimy and unpalatable, so i only use raw (albeit sometimes frozen first) greens in my smoothies, and eat my cooked greens elsewhere.